And now, a major headline for the millions of americans battling depression. 1 in 10 americans take antidepress antidepressants, but they can take weeks or months to bring relief. Well, now, the national institutes of health is saying they're trying a new kind of medication that may bring relief much faster. Abc's chief medical editor dr. Richard besser tells us more. Reporter: A lifetime of depression lifting in just a few minutes. Dennis, suffering for years, had tried pretty much every antidepressant on the market. No response. They never helped me at all. Reporter: But at the national institutes for health, they're trying out a whole new class of antidepressants. Drugs that may offer a new path to fighting depression, fast. A couple hours? Yes, that's all it takes, instead of a couple weeks, we can achieve the same thing in a few hours. Reporter: Typical antidepressants target the seratonin in your brain, a chemical that controls happiness. But you can't tell if the drug is working for four to six weeks. But this new drug is working in a completely different way, targeting the glutamate system, working on neurons that control mood. They seem to show results within hours. For dennis, it's meant a glimpse of a whole new life. I can get up in the morning, I can return calls, I can do the things that people do without impairment. It doesn't feel like I have to fight in order to do those routine tasks. Reporter: Dr. Richard besser, abc news, washington. Now, it's important to note that the drugs are only available right now in clinical trial. Dennis, if e ever becomes depressed again, he can watch the videos, see himself being happy and give himself hope.

This transcript has been automatically generated and may not be 100% accurate.